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PURE Study Further Exonerates Dairy Fat: Undeterred, The AHA Persists In Vilifying All Saturated Fat

The skeptical cardiologist had been avoiding reader pleas to comment on a paper recently published in the Lancet from the PURE study which showed that full fat dairy consumption is associated with a lower risk of mortality and cardiovascular disease. It felt like beating a dead horse since  I’ve been writing for the last 5 years that the observational evidence nearly unanimously shows that full fat dairy is associated with less abdominal fat, lower risk of diabetes and lower risk of developing vascular complications such as stroke and heart attack. However, since bad nutritional advice in this area stubbornly persists and the PURE study is so powerful and universally applicable, I felt compelled to post my observations.

What Did the PURE Study Show?

The PURE (Prospective Urban Rural Epidemiology)  study enrolled 136, 00 individuals aged 35–70 years from 21 countries in five continents. Dietary intakes of dairy products ( milk, yoghurt, and cheese) were recorded.. Food intake was stratified  into whole-fat and low-fat dairy. The primary outcome was the composite of mortality or major cardiovascular events.

Consumption of 2 servings of dairy per day versus none was associated with a 16% lower risk of the primary outcome. The high dairy consumers had an overall 17% lower risk of dying. They had a 34% lower risk of stroke.

People whose only dairy consumption consisted of  whole-fat products had a significantly lower risk of the composite primary endpoint (29%).

Here’s how one of the authors of the PURE study summarized his findings (quoted in a good summary at TCTMD)

“We are suggesting that dairy consumption should not be discouraged,” lead investigator Mahshid Dehghan, PhD (McMaster University, Hamilton, Canada), told TCTMD. “In fact, it should be encouraged in low-to-middle income countries, as well as in high-income countries among individuals who do not consume dairy. We have people in North America and Europe who are scared of dairy and we would tell them that three servings per day is OK. You can eat it, and there are beneficial effects. Moderation is the message of our study.”

 

Despite these recent  findings and the total lack of any previous data that indicates substituting low or no fat dairy for full fat dairy is beneficial,  the American Heart Association (AHA)and major nutritional organizations continue to recommend skim or low fat cheese, yogurt and milk over full fat , non-processed  dairy products.

The AHA Continues Its Misguided Vilification Of All Saturated Fat

Medpage today quoted an AHA spokesman as saying in response to the PURE study:

“Currently with the evidence that we have reviewed, we still believe that you should try to limit your saturated fat including fat that this is coming from dairy products,” commented Jo Ann Carson, PhD, of UT Southwestern Medical Center in Dallas and a spokesperson for the American Heart Association.

“It is probably wise and beneficial to be sure you’re including dairy in that overall heart-healthy dietary pattern, but we would continue to recommend that you make lower fat selections in the dairy products,” Carson told MedPage Today regarding the study, with which she was not involved.

 

What is their rationale? A misguided focus on macronutrients. For decades these people have been preaching that saturated fat is bad and unsaturated fat is good. All saturated fat is bad. All unsaturated fat is good.

To deem even one product which contains a significant amount of saturated fat as acceptable would undermine the public’s confidence in the saturated fat dogma.

Bad Nutritional Advice From The AHA Is Not New

Of course, the AHA has been notoriously off base on its nutritional advice for decades. selling its “heart-check” seal of approval to sugar-laden cereals such as Trix, Cocoa Puffs, and Lucky Charms and promoting trans-fat laden margarine. These products could qualify as heart-healthy because they were low in cholesterol and saturated fat.

To this day, the AHA’s heart-check program continues to promote highly processed junk food as heart-healthy while raking in millions of dollars from food manufacturers.

The AHA’s heart-check program is still using low cholesterol as a criteria for heart-healthy food whereas the 2015 Dietary Guidelines concluded that dietary cholesterol intake was no longer of concern.

Why would anyone believe the AHA’s current nutritional advice is credible given the historical inaccuracy of the program?

I’ve noticed that the dairy industry has done nothing to counter the idea that Americans should be consuming skim or low fat dairy product and discussed this with a dairy farmer who only sells full fat products a few years ago.

I posted his comments on this in my blog In April, 2016 and thought I would repost that posting for newer readers below:

 

The Skim Milk Scam:Words of Wisom From a Doctor Dairy Farmer

 

Full fat dairy is associated with less abdominal fat, lower risk of diabetes and lower risk of developing vascular complications such as stroke and heart attack.
quart_whole_milk_yogurt-293x300I’ve been consuming  full fat yogurt and milk  from Trader’s Point Creamery in Zionsville, Indiana almost exclusively since visiting the farm and interviewing its owners a few years ago.

Dr. Peter(Fritz) Kunz, a plastic surgeon, and his wife Jane, began selling milk from their farm after researching methods for rotational grazing , a process which allows  the cows to be self-sustaining: the cows feed themselves by eating the grass and in turn help fertilize the fields,  . After a few years of making sure they had the right grasses and cows, the Kunz’s opened Traders Point Creamery in 2003.

Two more studies (summarized nicely on ConscienHealth, an obesity and health blog)  came out recently solidifying the extensive data supporting the health of dairy fat and challenging the nutritional dogma that all Americans should be consuming low-fat as opposed to full fat dairy.

The Dairy Industry’s Dirty Little Secret

Dr. Kunz opened my eyes to the dirty little secret of the dairy industry when i first talked to him: dairy farmers double their income by allowing milk to be split into its fat and non-fat portions therefore the industry has no motivation to promote full fat dairy over nonfat dairy.

Recently, I  presented him with a few follow-up questions to help me understand why we can’t reverse the bad nutritional advice to consume low-fat dairy.

Skeptical Cardiologist: “When we first spoke and I was beginning my investigation into dairy fat and cardiovascular disease you told me that most dairy producers are fine with the promotion of non fat or low fat dairy products because if consumers are choosing low fat or skim dairy this allows the dairy producer to profit from the skim milk production as well as the dairy fat that is separated and sold for butter, cheese or cream products.”
I  don’t have a clear idea of what the economics of this are. Do you think this, for example, doubles the profitability of a dairy?

Dr. Kunz: “Yes, clearly. Butter, sour cream, and ice cream are highly profitable products… All these processes leave a lot of skim milk to deal with, and the best opportunity to sell skim milk is to diet-conscious and heart-conscious people who believe fat is bad.”

Skeptical Cardiologist:” I’ve been baffled by public health recommendations to consume low fat dairy as the science would suggest the opposite. The only reason I can see that this persists is that the Dairy Industry Lobby , for the reason I pointed out above, actually has a vested interest from a profitability standpoint in lobbying for the low fat dairy consumption.. Do you agree that this is what is going on? ”

 
Dr. Kunz: “Yes, definitely. The obsession with low-fat as it relates to diet and cardiac health has been very cleverly marketed. Fat does NOT make you fat.

Skeptical Cardiologist: “Also, I have had trouble finding out the process of production of skim milk. I’ve come across sites claiming that the process involves injection of various chemical agents but I can’t seem to find a reliable reference source on this. Do you have any information/undestanding of this process and what the down sides might be? I would like to be able to portray skim milk as a “processed food” which, more and more, we seem to be recognizing as bad for us.”

 

Dr. Kunz: “The PMO pasteurized milk ordinance states that when you remove fat you have to replace the fat soluble vitamins A & D. Apparently the Vitamin A & D have to be stabilized with a chemical compound to keep them miscible in basically an aqueous solution. The compound apparently contains MSG!! We were shocked to find this out and it further confirmed that we did not want to do a reduced fat or skim milk product.”

Skeptical Cardiologist: ” Any thoughts on A2? Marion Nestle’, of Food Politics fame, was recently in Australia where there is a company promoting A2 milk as likely to cause GI upset. It has captured a significant share of the Aussie market.”

 

Dr. Kunz: “We have heard of this and have directed our farm to test and replace any A1 heterozygous or homozygous cows.  We believe that very few of our herd would have A1 genetics because of the advantage of using heritage breeds like Brown Swiss and Jersey instead of Holstein.  Because few people are actually tested for lactose intolerance and because of the marketing of A2, it’s imperative not to be left behind in this – whether or not it turns out to be a true and accurate cause of people’s GI upset.

Skeptical Cardiologist:” I like that your milk is nonhomogenized. Seems like the less “processing” the better for food.  I haven’t found any compelling scientific reasons to recommend it to my patients, however. Do  you have any?”

 

Dr. Kunz: The literature is fairly old on this subject, but xanthine oxidase apparently can become encapsulated in the fat globules and it can be absorbed into the vascular tree and cause vascular injury.  I will look for the articles.  Anyway, taking your milk and subjecting it to 3000-5000 psi (homogenization conditions) certainly causes damage to the delicate proteins and even the less delicate fat globules.  Also remember that dietary cholesterol is not bad but oxidized cholesterol is very bad for you. That’s why overcooking egg yolks and high pressure spray drying to make powder products can be very dangerous – like whey protein powders that may contain some fats.

Skeptical Cardiologist: I spend a fair amount of time traveling in Europe and am always amazed that their milk is ultrapasteurized and sits unrefrigerated on the shelves. any thoughts on that process versus regular pasteurization and on pasteurization in general and its effects on nutritional value of dairy.

Dr. Kunz :“Absolutely crazy bad and nutritionally empty.. don’t know why anyone would buy it. The procedure is known as aseptic pasteurization and is how Nestle makes its wonderful Nesquik. If they made a full fat version of an aseptically pasteurized product it may have more oxidized cholesterol and be more harmful than no fat!!”
So there you have it, Straight from the  doctor dairy farmer’s mouth:
Skimming the healthy dairy fat out of  milk is a highly profitable process. Somehow, without a shred of scientific support,  the dairy industry, in cahoots with misguided and close-minded nutritionists, has convinced the populace that this ultra-processed skim milk pumped full of factory-produced synthetic vitamins is healthier than the original product.
Lactosingly Yours
-ACP
The two  recent articles (mentioned in this post) supporting full fat dairy are:

Circulating Biomarkers of Dairy Fat and Risk of Incident Diabetes Mellitus Among US Men and Women in Two Large Prospective Cohorts

which concluded ‘In two prospective cohorts, higher plasma dairy fatty acid concentrations were associated with lower incident diabetes. Results were similar for erythrocyte 17:0. Our findings highlight need to better understand potential health effects of dairy fat; and dietary and metabolic determinants of these fatty acids

and from Brazilian researchers

Total and Full-Fat, but Not Low-Fat, Dairy Product Intakes are Inversely Associated with Metabolic Syndrome in Adults1

Dear Dr. Gottlieb, Full Fat Dairy is “Healthy”. Why Are You Pushing Low-Fat Dairy?

By all accounts, Scott Gottlieb, the Trump appointed director of the FDA is doing a good job.

Vox points out, he has announced substantial FDA moves to reduce cigarette consumption and is committed to improving competition in generic drugs.

However, he gave a recent speech at the National Food Policy Conference  on “Reducing the Burden of Chronic Disease” which indicates he is misinformed on crucial aspects of nutritional science.

Gottlieb indicated he wanted the FDA to play a bigger role in guiding Americans to eat a healthier diet to reduce the burden of chronic disease.

To facilitate this he is looking to define what foods are “healthy”:

We’re keeping all these considerations in mind as we pursue rulemaking to update the definition of “healthy” so it’s based on nutrition criteria and food considerations that are more up-to-date than those being used for the current definition….

Once updating the definition, Gottlieb wants to label food as “healthy” In a way that makes it easier for consumers to understand:

To address this, we’ve had discussions about whether there should be a standard icon or symbol for the word “healthy” that everyone could use on food packages.

Gottlieb goes on to bemoan a focus on nutrients rather than foods but in the very  next sentence recommends a food, dairy, in a form that has one important nutrient stripped from it-fat.

Traditionally, we’ve focused primarily on the nutrients contained in food in considering what is healthy. But people eat foods, not nutrients.

This is why we’re asking the important question of whether a modernized definition of “healthy” should go beyond nutrients to better reflect dietary patterns and food groups, like whole grains, low fat dairy, fruits and vegetables and healthy oils?

Obviously, the first step in getting Americans to eat healthier is to make sure you are doling out the correct advise and in his speech Dr. Gottlieb indicates he has bought into  long-standing fundamental errors. I wrote him the following letter hoping to correct these errors.


Dear Dr. Gottlieb,

Congratulations on your recent appointment as FDA director and kudos for your fine work to date. I read your recent comments on developing an updated definition of “healthy” and the importance of  conveying that information to American consumers  I applaud your efforts in this area as well as your ongoing efforts to limit cigarette smoking and improve generic competition.

I am fine with guiding consumers to healthy foods but I beg of you, let this determination of what is healthy be guided by the actual science, not prior dogma.

In your recent speech you indicate that Americans are not consuming enough dairy and you recommend low-fat dairy which implies that you and the FDA believe that scientific studies have demonstrated that dairy fat is unhealthy.

Five years ago I, too , thought dairy fat was unhealthy and recommended my patients avoid butter, full-fat yogurt and cheese. However, when challenged on this belief, I reviewed the scientific literature on dairy fat and cardiovascular disease.

It turns out when objectively analyzed (as I have written about here and here ) there is no scientific evidence that supports the concept that dairy processed to remove dairy fat is healthier than the original unadulterated product.

In fact, evidence suggests full fat dairy reduces central obesity, diabetes, cardiovascular disease and atherosclerosis in general.

As a result of misguided recommendations to avoid dairy fat, it is virtually impossible in most grocery stores to find full fat yogurt or milk. The vast majority of the dairy aisle is devoted to various low or non fat concoctions which have had loads of sugar and chemicals added and are arguably worse than a Snickers bar.

Dr. Gottlieb ,I am not cherry-picking the data here or relying on out of date studies. I’ve reviewed everything I can find on this issue and reviewed it without bias. Evidence continues to accumulate supporting the healthiness of full fat dairy.

For example, here’s a 2018 review from researchers totally unaffiliated with the dairy industry which asks the question “Dairy Fats and Cardiovascular Disease: Do We Really Need to Be Concerned?”

After a exhaustive review they conclude the answer is no.

recent research and meta-analyses have demonstrated the benefits of full-fat dairy consumption, based on higher bioavailability of high-value nutrients and anti-inflammatory properties. … In general, evidence suggests that milk has a neutral effect on cardiovascular outcomes but fermented dairy products, such as yoghurt, kefir and cheese may have a positive or neutral effect.

Flawed Reasons for Low Fat Dairy Recommendations

As I have written previously, I believe there are three reasons for the failure of major nutritional recommendations such as the 2015  Dietary Guidelines For Americans  to correct previously  flawed advice to choose  non or low-fat dairy over full fat:

1. In  few randomized dietary studies showing benefits of a particular diet over another, non fat or low fat dairy was recommended along with a portfolio of other healthy dietary changes.

The overall benefit of the superior diet had nothing to do with lowering the dairy fat but was due to multiple other changes.

2. The dairy industry has no motivation to promote full fat dairy. In fact, they do better financially when they can take the fat out of milk and sell it for other purposes such as butter, cheese, and cream. (Please read my interview with a plastic surgeon dairy farmer on the skim milk scam here.)

3. Saturated fat is still mistakenly being treated as a monolithic nutritional element.  Although dairy fat is mostly saturated, the individual saturated fats vary widely in their effects on atherogenic lipids and atherosclerosis. In addition, the nature of the saturated fat changes depending on the diet of the cow.

4. Since authorities have been making this low fat dairy recommendation for so long they are extremely reluctant to reverse their advice. It lowers their credibility.

There Is No Scientific Consensus On What Constitutes A Healthy Oil

Finallly, Dr. Gottlieb, I would like to briefly point out that there is considerable ongoing scientific debate about what constitutes a “healthy oil.”

I summarized this last year on a post on coconut oil (which I fear you will also pronounce “unhealthy”).

In many respects, the vilification of coconut oil by federal dietary guidelines and the AHA resembles the inappropriate attack on dairy fat and is emblematic of the whole misguided war on dietary fat. In fact, the new AHA advisory  after singling out coconut oil goes on to cherry-pick the data on dairy fat and cardiovascular disease in order to  support their faulty recommendations for choosing low or nonfat dairy.

Canola and corn oil, the products of extensive factory processing techniques, contain mostly mono or polyunsaturated fats which have been deemed “heart-healthy” on the flimsiest of evidence.

The most recent data we have on replacing saturated fat in the diet with polyunsaturated fat comes from the Minnesota Coronary Experiment performed from 1968 to 1973, but published in 2016 in the BMJ.

Data from this study, which substituted liquid corn oil in place of the usual hospital cooking fats, replaced corn oil margarine for butter and added corn oil to numerous food items, showed no overall benefit in reducing mortality. In fact, individuals over age 65 were more likely to die from cardiovascular disease if they got the corn oil diet.

So, Dr. Gottlieb, please continue your efforts to make Americans healthier but make sure the current scientific evidence actually supports your recommendations. Keep in mind, the disastrous public health experiments of previous decades.


Skeptically Yours,

-ACP

N.B. Some of my posts on dairy fat are below.

Dairy Fat Makes You Thinner

The Skim Milk Scam

More Evidence That Diary Fat is associated with a lower risk of heart disease

What happens to cholesterol levels when you switch to low or non fat dairy?

Dietary Guidelines 2015: Why Lift Fat and cholesterol limits but still promote low fat dairy?

In defense of real cheese.


h/t to the always excellent Conscien Health for bringing Gottlieb’s speech to my attention.


Credit for the featured image of dairy cows from the wonderful Trader’s Point Creamery

The Bad Food Bible: A Well-Written, Sensible and Science-Based Approach To Diet

The skeptical cardiologist has been searching for some time for a book on diet that he can recommend to his patients. While I can find books which have a lot of useful content, usually the books mix in some totally unsubstantiated advice with which I disagree.

I recently discovered a food/diet/nutrition book which with I almost completely agree. The author is Aaron Carroll,  a pediatrician, blogger on health care research (The incidental Economist) and a Professor of Pediatrics and Associate Dean for Research Mentoring at Indiana University School of Medicine.

He writes a regular column for the New York Times and covers various topics in health care. His articles are interesting,  very well written and researched and he often challenges accepted dogma.

Like the skeptical cardiologist, he approaches his topics from an unbiased perspective and utilizes a good understanding of the scientific technique along with a research background to bring fresh perspective to health-related topics.

Last last year he wrote a column, within which I found the following:

Studies of diets show that many of them succeed at first. But results slow, and often reverse over time. No one diet substantially outperforms another. The evidence does not favor any one greatly over any other.

That has not slowed experts from declaring otherwise. Doctors, weight-loss gurus, personal trainers and bloggers all push radically different opinions about what we should be eating, and why. We should eat the way cave men did. We should avoid gluten completely. We should eat only organic. No dairy. No fats. No meat. These different waves of advice push us in one direction, then another. More often than not, we end up right where we started, but with thinner wallets and thicker waistlines.

I couldn’t agree more with this assessment and as I surveyed the top diet books on Amazon recently, I saw one gimmicky, pseudoscientific  diet after another. From the Whole30 approach (which illogically  completely eliminates any beans and legumes, dairy products,  alcohol, all grains, and starchy vegetables like potatoes (see how absurd this diet is here)) to Dr. Gundry’s Plant Paradox (aka lectin is the new gluten (see here for James Hambling’s wonderful Atlantic article on the huckster’s latest attempt to scare you into buying his useless supplements).

It turns out Carroll published a useful book recently, The Bad Food Bible which critically examines diet and I agree with the vast majority of what is in it.

The first three chapters are on butter, meat, eggs and salt. His conclusions on how we should approach these 4 are similar to ones I have reached and written about on this site (see here for dairy, here for meat, here for eggs and here for salt).  Essentially, the message is that the dangers of these four foods have been exaggerated or nonexistent, and that consuming them in moderation is fine.

The remaining chapters cover topics I have pondered extensively,  but have not written about: including gluten, GMOs, alcohol, coffee, diet-soda and non-organic foods.

I agree with his assessments on these topics. Below, I’ll present his viewpoint along with some of my own thoughts in these areas.

Gluten

Carroll does a good job of providing a scientific, but lay-person friendly background to understanding the infrequent (1 of 141 Americans), but quite serious gluten-related disorder, celiac disease.

However, surveys show that up to one-third of Americans, the vast majority of whom don’t have celiac disease, are seeking “gluten-free” foods, convinced that this is a healthier way of eating. Carroll points out that there is little scientific support for this; there are some individuals who are sensitive to wheat/gluten, but these are rare.

He concludes:

“If you have celiac disease, you need to be on a gluten-free diet. If you have a proven wheat allergy, you need to avoid wheat. But if you think you have gluten sensitivity? You’d probably be better off putting your energy and your dollars toward a different diet. Simply put, most people who think they have gluten sensitivity just don’t.

I do agree with him that the “gluten-free” explosion of foods (gluten-free sales have doubled from 2010 to 2014) is not justified.

However, I must point out that my 92 year old father has recently discovered that he has something that resembles gluten sensitivity. About a year ago, he noted that about one hour after eating a sandwich he would feel very weak and develop abdominal discomfort/bloating. He began suspecting these symptoms were due to the bread and experimented with different bread types without any symptom relief.

Finally, he tried gluten-free bread and the symptoms resolved.

If you have engaged in this type of observation and experimentation on your self, and noted improved symptoms when not consuming gluten, then I think you’re justified in diagnosing gluten sensitivity, and by all means consider minimizing/avoiding wheat.

GMOS

Carroll begins his chapter on genetically modified organisms (GMOs) with a description of the droughts that plagued India in the 1960s and the efforts of Norman Borlaug to breed strains of wheat that were resistant to fungus and yielded more grain. By crossbreeding various strains of wheat he was able to develop a “semi-dwarf” strain that increased what was produced in Mexico by six-fold.

Despite the fact that numerous scientific and health organizations around the world have examined the evidence regarding the safety of genetically modified organisms (GMOs) and found them to be completely safe, there remains a public controversy on this topic. In fact a Pew Poll found that while 88% of AAAS scientists believe that GMOs are safe for human consumption, only 37% of the public do – a 51% gap, the largest in the survey.

This gap is largely due to an aggressive anti-GMO propaganda campaign by certain environmental groups and the organic food industry, a competitor which stands to profit from anti-GMO sentiments. There is also a certain amount of generic discomfort with a new and complex technology involving our food.

The National Academy of Sciences analyzed in detail the health effects of GMOs in 2016. Their report concludes:

While recognizing the inherent difficulty of detecting subtle or long-term effects in health or the environment, the study committee found no substantiated evidence of a difference in risks to human health between currently commercialized genetically engi-neered (GE) crops and conventionally bred crops, nor did it find conclusive cause-and-effect evidence of environmental problems from the GE crops. GE crops have generally had favorable economic outcomes for producers in early years of adoption, but enduring and widespread gains will depend on institutional support and access to profitable local and global markets, especially for resource-poor farmers

Carroll does a good job of looking at the GMO issue from all sides. He touches on environmental downsides related to herbicide-resistant GMO crops and the problems created by patenting GMO seeds, but asserts that “these are the result of imperfect farming and the laws that regular agribusiness, not of GMOS themselves.”

Ultimately, despite these concerns, I agree with Carroll’s conclusion that:

“Foods that contain GMOs aren’t inherently unhealthy, any more are  than foods that don’t contain them. The companies that are trying to see you foods by declaring them ‘GMO-free” are using the absence of GMOs to their advantage–not yours.”

Alcohol, Coffee, and Diet-Soda

Carroll does a good job of summarizing and analyzing the research for these three topics and reaches the same conclusions I have reached in regard to coffee, alcohol and diet-soda:

-alcohol in moderation lowers your risk of  dying, primarily by reducing cardiovascular death

-coffee, although widely perceived as unhealthy, is actually good for the vast majority of people

For those seeking more details a few quotes


on alcohol:

“Taken together, all of this evidence points to a few conclusions. First, the majority of the research suggests that moderate alcohol consumption is associated with decreased rates of cardiovascular disease, diabetes, and death. Second, it also seems to be associated with increased rates of some cancers (especially breast cancer), cirrhosis, chronic pancreatitis, and accidents, although this negative impact from alcohol seems to be smaller than its positive impact on cardiovascular health. Indeed, the gains in cardiovascular disease seem to outweigh the losses in all the other diseases combined. The most recent report of the USDA Scientific Advisory Panel agrees that “moderate alcohol consumption can be incorporated into the calorie limits of most healthy eating patterns.”

Keep in mind that moderate consumption is up to one drink per day for women, and two drinks for men (my apologies to women in general and the Eternal Fiancee’ of the Skeptical Cardiologist in particular) and be aware of what constitutes “one drink.”

Also keep in mind that any alcohol consumption raises the risk of atrial fibrillation (see here) and that if you have a cardiomyopathy caused by alcohol you should avoid it altogether.


on coffee:

“It’s time people stopped viewing coffee as something to be limited or avoided. It’s a completely reasonable part of a healthy diet, and it appears to have more potential benefits than almost any other beverage we consume.
Coffee is more than my favorite breakfast drink; it’s usually my breakfast, period. And I feel better about that now than ever before. It’s time we started treating coffee as the wonderful elixir it is, not the witch’s brew that C. W. Post made it out to be.”

Strangely enough, coffee is usually my breakfast as well (although I recommend against adding titanium oxide to your morning java).  Why am I not compelled to consume food in the morning?  Because breakfast is not the most important meal of the day and I don’t eat until I’m hungry.


on diet-soda:

Carroll notes that many Americans are convinced that artificial sweeteners are highly toxic:

“no article I’ve written has been met with as much anger and vitriol as the first piece I wrote on this subject for the New York Times, in July 2015, in which I admitted, “My wife and I limit our children’s consumption of soda to around four to five times a week. When we let them have soda, it’s . . . almost always sugar-free.”

He notes, as I have done, that added sugar is the real public enemy number one in our diets. He reviews the scientific studies that look at toxicity of the various artificial sweeteners and finds that they don’t convincingly prove any significant health effects in humans.

Some believe that artificial sweeteners contribute to obesity, but the only evidence supporting this idea comes from observational studies. For many reasons, we should not highly value observational studies but one factor, “reverse causation,” is highly likely to be present in studies of diet sodas. If diet soda consumption is associated with obesity, is it the cause, or do those who are obese tend to drink diet soda. Observational studies cannot answer this question but randomized studies can.

Carroll points out that:

the randomized controlled trials (which are almost always better and can show causality) showed that diet drinks significantly reduced weight, BMI, fat, and waist circumference.”

Simple Rules For Healthy Eating

Carroll concludes with some overall advice for healthy eating:

-Get as much of your nutrition as possible from a variety of completely unprocessed foods

-Eat lightly processed foods less often

-Eat heavily processed foods even less often

-Eat as much home-cooked food as possible, preparing it according to rules 1, 2, and 3

-Use salt and fats, including butter and oil, as needed in food preparation

-When you do eat out, try to eat at restaurants that follow the same rules

-Drink mostly water, but some alcohol, coffee, and other beverages are fine

-Treat all calorie-containing beverages as you would alcohol

-Eat with other people, especially people you care about, as often as possible

These are solid, albeit not shocking or book-selling, rules that  correspond closely to what I have adopted in my own diet.

In comparison to the bizarre advice from nutrition books which dominate the best-selling diet books, I found The Bad Food Bible to be a consistent, well-written, extensively researched, scientifically-based, unbiased guide to diet and can highly recommend it to my readers and patients.

Semibiblically Yours,

-ACP

The Harvard T.H. Chan School of Public Health Now Recommends Full Fat Dairy For Your Kid’s Lunch Boxes

The skeptical cardiologist became overjoyed while reading an email from The Harvard T.H. Chan School of Public Health (THTHCSPH) which outlined  their recommendations for packing kids‘ lunch boxes.:

The Kid’s Healthy Eating Plate was created as a fun and easy guide to encourage children to eat well and keep moving. The plate guidelines emphasize variety and quality in food choices.

The majority of the recommendations were pretty straightforward and mainstream:

The formula is simple: Fill half your plate (or lunch box) with colorful fruits or vegetables(aim for two to three different types). Fill about one-quarter with whole grains like whole grain pasta, brown rice, or quinoa, and the remaining quarter with healthy proteinslike beans, nuts, fish or chicken. Healthy fatsand a small amount of dairy (if desired) round out a tasty meal that will fuel an active, healthy lifestyle.

What caught my attention was the comment about dairy.

The dreaded words skim or low-fat did not appear in the sentence!

It would appear that a highly respect and mainstream source of nutritional advice is not making the typical (and scientifically unsupported ) recommendation to consume low fat or skim dairy products!

Indeed, if we look at their expanded comments on dairy they read:

Incorporating dairy (if desired). For example: unflavored milk, plain Greek yogurt, small amounts of cheese like cottage cheese, and string cheese.

No mention of fat content. Zip. Zero. To me, if you don’t put non fat low fat or skim next to the word diary it implies full fat.

Following their yogurt link we find no reference to preferentially consuming low fat yogurt despite the fact that the vast majority of yogurt sold in the US has been processed to remove healthy dairy fat, something the THCHSPH must be painfully aware of. (My wonderful MA Jenny’s husband, Frank, until very recently was unable to find full fat yogurt at Schnuck’s.)

As I pointed out here, a huge scam was foisted on Americans when allegedly healthy non fat yogurt filled with added sugar began to be promoted as a healthy treat.

It is almost  as if the THTHCSPH  has become agnostic about dairy fat and therefore is trying not to make recommendations.

Elsewhere on the THTHCSPH site however the old unwarranted advice  to avoid dairy fat rears its ugly head. On a page devoted to calcium we read:

Many dairy products are high in saturated fats and a high saturated fat intake is a risk factor for heart disease”

Then this interesting (and ?ironic) observation:

And while it’s true that most dairy products are now available in fat-reduced or nonfat options, the saturated fat that’s removed from dairy products is inevitably consumed by someone, often in the form of premium ice cream, butter, or baked goods.

Strangely, it’s often the same people who purchase these higher fat products who also purchase the low-fat dairy products, so it’s not clear that they’re making great strides in cutting back on their saturated fat consumption.

The THTHCSPH seems conflicted, as well they should. They want to keep up the nutritional party line that they have been spouting for 30 years that all saturated fats are bad but they now realize that supporting non fat dairy products has likely worsened rather than improved the diet of millions of Americans.

Galactosely Yours,

-ACP

N.B. The overall Kid’s healthy eating plate is not likely to be a favorite of kids  and I disagree with some aspects of it.

Namely, I think it is fine to have red meat and processed meats in moderation and I wouldn’t push the pasta, rice, and bread.

 

 

 

 

The Skeptical Cardiologist Gives Dietary Thanks

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Something I’m not thankful for:Vitamin Water. It consists of water, 32 grams of sugar and lots of useless vitamins. People, stop buying this stuff. You are only helping Coca-Cola fill Americans with TOO MUCH SUGAR!

On this fourth Thursday of November, 2015 the skeptical cardiologist would like to record some Thanksgiving thanks.

  • I’m thankful I’m not a turkey today.

I hear Americans consume 45 million turkeys on Thanksgiving, one sixth of the total during the year.

Americans have embraced turkeys nutritionally because they are low in saturated fat and provide lots of protein. Most nutritional advice suggests avoiding the dark meat and the skin, but I prefer to seek those portions out because they taste better and as I pointed out here last Thanksgiving, Up To Date, the major medical reference for physicians, now says “Don’t Worry About Saturated Fat Consumption.”

  • I’m thankful that dairy fat is good for you.
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The Eternal Fiancee’ (For whose presence in my life I am eternally grateful) Cutting Tomatoes for Crabmeat Ravigote, a traditional cajun dish full of cholesterol from eggs and crustaceans

The eternal fiancee’ and I took a cooking class in New Orleans (New Orleans School of Cooking) recently, and butter seemed to be the basis for every dish we cooked: from dark roux in our gator sauce piquante’, to the blonde roux in the Louisiana meat pies.

When the  teacher of the class, chef Austin, asked the students to introduce themselves, I told him I was the skeptical cardiologist and I was there to evaluate New Orleans dishes for my patients.

Chef Austin didn’t think I would be recommending the dishes to my patients, but I heartily endorsed them ( See here and here).

  • I’m thankful that cholesterol is no longer considered by the Dietary Guidelines for Americans Committee (DGAC) a nutrient of concern.

All may eat eggs and crustaceans without fear now.

However, there is a backlash from the vegans on this revelation: the weirdly named Physicians Committee for Responsible Medicine (PCRM’s goal seems to be elimination of all animal testing and consumption, not responsible medicine) has erected billboards in Texas targeting the chairman of the House Agriculture Committee (K Michael Conoway (R-TX)).

The final guidelines have yet to be issued, but I’m betting on the egg industry over the vegans on this one, despite the billboards.

  • I’m thankful that studies continue to come out showing coffee is not bad for you.

This study, for example, followed 90 thousand Japanese for 19 years and found that the more coffee you drink, the lower your risk of dying-from cardiac, respiratory and cerebrovascular disease. Those consuming 3-4 cups/day were 25% less likely to die than those who never drank coffee.

-I’m thankful that correlation does not equal causation.

This means that I don’t have to stop eating bacon or beef brisket (assuming I am insensitive to global sustainability concerns). On the other hand, that association between higher coffee consumption  and lower risk of dying over 19 years doesn’t mean that drinking more coffee is actually lowering the risk; but it’s certainly not increasing it.

Screenshot 2015-11-26 11.50.04Finally, I’m thankful that moderate alcohol consumption is good for your heart and I raise a toast of gratitude to patient patients, readers and correspondents.

-ACP

 

Saturated Fat: Traditionalists versus Progressives

Why is death from coronary heart disease declining in the US at the same time that obesity and diabetes rates are climbing?

Two editorials recently published in The Lancet show the widely varying opinions on the optimal diet for controlling obesity , diabetes and coronary heart disease that experts on nutrition, diabetes and heart disease hold.

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Typical innocent and usual suspects rounded up in the war on fat: Cheese-data show it lower heart disease risk Full fat yogurt (Trader’s Point Creamery)-data show it is associated with lower heart disease risk Butter-Delicious. Used in moderation not a culprit.

The first paper contains what I would  consider the saturated fat “traditionalist” viewpoint. This is a modification of the misguided concept that was foisted on the American public in the 1980s and resulted in the widespread consumption of industrially produced trans-fats and high sugar junk food that was considered heart healthy.

The traditionalists have shifted from condemning all fats to vilifying only saturated and trans fats. They would like to explain at least part of the reduction in coronary heart mortality as due to lower saturated fat consumption and the accompanying lowering of LDL (“bad”) cholesterol.

The SFA traditionalists fortunately are in decline and more and more in the last five years, prominent thinkers, researchers and scientists working on the connection between diet and the heart believe saturated fats are neutral but sugar and refined carbohydrates are harmful in the diet.

Darius Mozzafarian, a highly respected cardiologist and epidemiologist, who is dean of the School of Nutrition Science and Policy at Tufts, wrote the second editorial and is what I would term a saturated fatty acid (SFA) progressive.

He makes the following points which are extremely important to understand and which I have covered in previous posts. I’ve included his supporting references which can be accessed here.

Fat Doesn’t Make You Fat, Refined Starches And Sugar Do

"Foods rich in refined starches and sugars—not fats—seem to be the primary culprits for weight gain and, in turn, risk of type 2 diabetes. To blame dietary fats, or even all   calories, is incorrect
Although any calorie is energetically equivalent for short-term weight loss, a food's long-term obesogenicity is modified by its complex effects on satiety, glucose–insulin responses, hepatic fat synthesis, adipocyte function, brain craving, the microbiome, and even metabolic expenditure Thus, foods rich in rapidly digestible, low-fibre carbohydrates promote long-term weight gain, whereas fruits, non-starchy vegetables, nuts, yoghurt, fish, and whole grains reduce       long-term weight gain.123
Overall, increases in refined starches, sugars, and other ultraprocessed foods; advances in food industry marketing; decreasing physical activity and increasing urbanisation in developing nations; and possibly maternal–fetal influences and reduced sleep may be the main drivers of obesity and diabetes worldwide".

There Are Many Different Kinds of Saturated Fats With Markedly Different Health Effects: It Makes No Sense to Lump Them All Together 

"SFAs are heterogeneous, ranging from six to 24 carbon atoms and having dissimilar biology. For example, palmitic acid (16:0) exhibits in vitro adverse metabolic effects, whereas medium-chain (6:0–12:0), odd-chain (15:0, 17:0), and very-long-chain (20:0–24:0) SFAs might have metabolic benefits.4 This biological and metabolic diversity belies the wisdom of grouping of SFAs based on a single common chemical characteristic—the absence of double bonds. Even for any single SFA, physiological effects are complex: eg, compared with carbohydrate, 16:0 raises blood LDL cholesterol, while simultaneously raising HDL cholesterol, reducing triglyceride-rich lipoproteins and remnants, and having no appreciable effect on apolipoprotein B,  5 the most salient LDL-related characteristic. Based on triglyceride-lowering effects, 16:0 could also reduce apolipoprotein CIII, an important modifier of cardiovascular effects of LDL and HDL cholesterol. SFAs also reduce concentrations of lipoprotein(a) ,6 an independent risk factor for coronary heart disease."

The Effects of Dietary Saturated Fats Depend on Complex Interactions With The Other Ingredients in Food

"Dietary SFAs are also obtained from diverse foods, including cheese, grain-based desserts, dairy desserts, chicken, processed meats, unprocessed red meat, milk, yoghurt, butter, vegetable oils, and nuts. Each food has, in addition to SFAs, many other ingredients and characteristics that modify the health effects of that food and perhaps even its fats. Judging the long-term health effects of foods or diets based on macronutrient composition is unsound, often creating paradoxical food choices and product formulations. Endogenous metabolism of SFAs provide further caution against oversimplified inference: for example, 14:0 and 16:0 in blood and tissues, where they are most relevant, are often synthesised endogenously from dietary carbohydrate and correlate more with intake of dietary starches and sugars than with intake of meats and dairy.4"

Dietary Saturated Fat Should Not Be a Target for Health Promotion

"These complexities clarify why total dietary SFA intake has little health effect or relevance as a target. Judging a food or an individual's diet as harmful because it contains more SFAs, or beneficial because it contains less, is intrinsically flawed. A wealth of high-quality cohort data show largely neutral cardiovascular and metabolic effects of overall SFA intake.7 Among meats, those highest in processing and sodium, rather than SFAs, are most strongly linked to coronary heart disease.7Conversely, higher intake of all red meats, irrespective of SFA content, increases risk of weight gain and type 2 diabetes; the risk of the latter may be linked to the iron content of meats.28 Cheese, a leading source of SFAs, is actually linked to no difference in or reduced risk of coronary heart disease and type 2 diabetes.910 Notably, based on correlations of SFA-rich food with other unhealthy lifestyle factors, residual confounding in these cohorts would lead to upward bias, causing overestimation of harms, not neutral effects or benefits. To summarise, these lines of evidence—no influence on apolipoprotein B, reductions in triglyceride-rich lipoproteins and lipoprotein(a), no relation of overall intake with coronary heart disease, and no observed cardiovascular harm for most major food sources—provide powerful and consistent evidence for absence of appreciable harms of SFAs."

Dietary Saturated Fats May Raise LDL cholesterol But This Is Not Important: Overall Effects On Obesity and Atherosclerosis Are What Matters

"a common mistake made by SFA traditionalists is to consider only slices of data—for example, effects of SFAs on LDL cholesterol but not their other complex effects on lipids and lipoproteins; selected ecological trends; and expedient nutrient contrasts. Reductions in blood cholesterol concentrations in Western countries are invoked, yet without systematic quantification of whether such declines are explained by changes in dietary SFAs. For example, whereas blood total cholesterol fell similarly in the USA and France between 1980 and 2000, changes in dietary fats explain only about 20% of the decline in the US and virtually none of that which occurred in France.11Changes in dietary fats11 simply cannot explain most of the reductions in blood cholesterol in Western countries—even less so in view of the increasing prevalence of obesity. Medication use also can explain only a small part of the observed global trends in blood cholesterol and blood pressure. Whether decreases in these parameters are caused by changes in fetal nutrition, the microbiome, or other unknown pathways remains unclear, thus highlighting a crucial and greatly underappreciated area for further investigation."

Dietary Saturated Fats Are Neutral For Coronary heart Disease Risk

Finally, SFA traditionalists often compare the effects of SFAs only with those of vegetable polyunsaturated fats, one of the healthiest macronutrients. Total SFAs, carbohydrate, protein, and monounsaturated fat each seem to be relatively neutral for coronary heart disease risk, likely due to the biological heterogeneity of nutrients and foods within these macronutrient categories.7Comparisons of any of these broad macronutrient categories with healthy vegetable fats would show harm,12 so why isolate SFAs? Indeed, compared with refined carbohydrates, SFAs seem to be beneficial.7

The overall evidence suggests that total SFAs are mostly neutral for health—neither a major nutrient of concern, nor a health-promoting priority for increased intake. 

Focusing On Reducing Saturated Fats Leads To Unhealthy Dietary Choices

I’ve written about this a lot. The most baffling aspect of this is the promotion of low or non-fat dairy.

There is no evidence that low fat dairy products are  healthier than full fat dairy products.

Non-fat yogurt filled with sugar should be considered a dessert, not a healthy food.

"Continued focus on modifying intake of SFAs as a single group is misleading—for instance, US schools ban whole milk but allow sugar-sweetened skim milk; industry promotes low-fat foods filled with refined grains and sugars; and policy makers censure healthy nut-rich snacks because of SFA content.13 "

It is extremely hard to change most people’s opinions on dietary fat.

My patients have been hearing the SFA traditionalist dogma for decades and thus it has become entrenched in their minds.

When I present to them the new progressive and science-based approach to fat and saturated fat some find it so mind boggling that they become skeptical of the skeptical cardiologist!

Hopefully, in the next few years, the progressive SFA recommendations will become the norm and maybe , some day in the not too distant future, the inexplicable recommendations for low-fat or non fat dairy will disappear.

As more data accumulates we may become SFA enthusiasts!

Saturatingly Yours,

-ACP

For another viewpoint (?from an SFA enthusiast) and  a detailed description of both editorials see Axel Sigurdsson’s excellent post here.

Dairy and the Paleo Delusion

The Paleo diet (primal/evolutionary) has become very popular in the last few years. Followers believe they are eating the way our stone age, or paleolithic, ancestors ate. Since our genes have not had time to evolve to match the drastic change in diet that occurred with the agricultural revolution, they argue, modern diets are making us sick and contributing to most of our chronic Western disease like atherosclerosis, diabetes and dementia.

True experts in evolutionary science have questioned most of the theoretical underpinnings of the Paleo movement. Marlene Zuk, an evolutionary biologist, has written an excellent critique in her recently published book “Paleofantasies: What Evolution Really Tells Us About Sex, Diet and How We Live.”

Dr. Zuk points out that there likely was no one single hunter-gatherer diet and that we have a very limited understanding of exactly what that diet consisted of. She also makes the point that this concept that at some point in the past, humans were perfectly adapted to their environment, is not true.

The Milk Paleofantasy

Although the Paleo movement is not monolithic on the topic, some of its leading figures are vehemently opposed to milk consumption.

For example, Loren Cordain (whose web site states that he is “widely acknowledged as one of the world’s leading experts on the natural human diet of our Stone Age ancestors”), has nothing but bad things to say about dairy and milk consumption. Cordain has a Ph.D in “health” and is quite a prolific author, having written “The Paleo Cure For Acne” (spoiler alert: the cure involves not drinking milk).

One major problem with the paleo concept of diet is the assumption that our genetic makeup has not changed or evolved over the last 10000 years.

It turns out that we are not stuck with the same genome of our caveman ancestors and that our ability to tolerate milk confirms this.

The Evolution of Lactose Tolerance

The main sugar in milk from all mammals is lactose. The ability to digest lactose depends on having the enzyme lactase present in the lining of the intestinal tract. All mammals at birth have lactase, but as they age, lactase production is reduced by around 90%. This loss of lactase leads to lactose intolerance.

Lactose that is not digested ends up being fermented by bacteria in the large intestines. This fermentation produces methane, hydrogen gases and other by-products, resulting in bloating, abdominal pain, and diarrhea.

Around 10-20,000 years ago, a mutation in the gene that controls production of lactase resulted in lactase persistence. Some of our paleolithic ancestors began noticing that they were lactose tolerant and could drink the milk of cattle that they had domesticated.

As Zuk writes:

Beginning about 7000 years ago, DNA studies of ancient bones reveal that there was a progressive increase in the frequency of lactase persistence. Increase in a genes frequency tends to correspond with a survival advantage suggesting that the ability to consume dairy prolonged lives.

Lactase persistence is present only in about 35% of the world’s population. It is common in Scandinavia and parts of Africa and the Middle East and about 90% of Americans have it.

The rapid increase in the dominant gene for lactase persistence in humans suggests that the Paleo concept of a genome stuck in the stone age is incorrect.

Stumbling onto a heart-healthy diet using Paleofantasies

Despite the lack of scientific support for the basic theories underpinning the movement, I do think the Paleo diet has some good points. For the most part, this is going to be a low-carb diet. Other areas I can agree with them on are:

-Avoid processed foods, added sugar, refined starches

-Eat lots of minimally processed vegetables

-Grass-fed beef is fine

-Wild game consumption is great (but wild game is hard to find)

But ultimately, the Paleos, as students of evolutionary biology, should be embracing the evolutionary changes humans underwent that allowed the consumption of dairy as adults.

Since Dietary Cholesterol Isn’t Important Can I Stop Taking My Cholesterol Drug

A year ago one of my patients began experiencing  chest pain when he walked up hills. Subsequent evaluation revealed that atherosclerotic plaque (95% narrowing of a major coronary artery ) was severely reducing the blood flow to his heart muscle and was the cause of his chest pain. When this blockage was opened up with a stent he no longer had the pain.

Along with other medications (aspirin and plavix to keep his stent open) I had him start atorvastatin, the generic version of Lipitor, a powerful statin drug that has been shown to prevent progression of atherosclerotic plaque and thereby reduce subsequent heart attacks, strokes and death in patients like him

I saw him in the office the other day in follow up and he was feeling great . He asked me “Doc I read  your post yesterday.s Since you say that cholesterol in the diet doesn’t matter anymore, does that mean I don’t have to take my cholesterol drug anymore.?”

His question gets at the heart of the  “diet-heart hypothesis”. The concept that dietary modification, with reduction of cholesterol and fat consumption can reduce coronary heart disease.

The science supporting this hypothesis has never been strong but the concept was foisted on the American public and was widely believed. It was accepted I would  say because it has a beautiful simplicity which can be summarized as follows:

“If you eat cholesterol and fat it  will enter  your blood stream and raise cholesterol levels. This excess cholesterol will then  deposit in your arteries, creating fatty plaque , clogging them and leading to a heart attack.”

This concept was really easy to grasp and simplified the public health recommendations.

However, cholesterol blood levels are determined more by cholesterol synthesized in the liver and predicting  how dietary modifications will effect these levels is not easy.

Since the public has had the diet-heart hypothesis fed to them for decades and given its beautiful simplicity it is hard to reverse this dogma. My patient’s question reflects a natural concern that if science/doctors got this crucial question so wrong, is everything we know about cholesterol treatment and heart disease wrong?

In other words, are doctors promoting a great cholesterol hoax?

Evidence Strongly Supports Statins in Secondary Prevention 

For my patient the science supporting taking a  cholesterol-lowering statin drug is very solid. There are multiple excellent studies showing that in patients with established coronary artery disease taking a statin drug substantially reduces their risk of heart attack and dying.

These studies are the kind that provide the most robust proof: randomized, prospective and blinded.

level of evidenceWhen cardiologists rate the strength of evidence for a certain treatment (as done for lifestyle intervention here) we use  a system that categorizes the evidence as Level A, B, or C quality.

LeveleA quality (or strong) evidence consists of multiple,large, well-done, randomized trials such as exist for statins in patients with coronary heart disease.

Level B Evidence comes from a single randomized trial or nonrandomized studies.

Level C evidence is the weakest and comes from “consensus opinion of experts, case studies or standard of care.”

When treatment recommendations are based on Level C evidence they are often reversed as more solid data is obtained. Level A recommendations almost always hold up over time.

The level of evidence supporting restricting dietary cholesterol and fat to reduce heart attacks and strokes has always been at or below Level C and now it is clear that it is insufficient and should be taken out of guideline recommendations.

Evidence Strongly Supports Atherogenic Cholesterol is Related to Coronary Heart Disease

There are other lines of evidence that strongly support  the concept that  LDL cholesterol (bad cholesterol) or an atherogenic form of LDL cholesterol is strongly related to the development of atherosclerosis. If you are born with really high levels you are at very high risk for coronary heart disease, conversely if you are born with mutations that cause extremely low levels you are highly unlikely to get coronary heart disease.

Thus, the cholesterol hypothesis as it relates to heart disease is very much till intact although the diet-heart hypothesis is not.

Conflating the Diet-Heart Hypothesis and the Cholesterol Hypothesis

There is an abundance of misinformation on the internet that tries to conflate these two concepts. Sites with titles like “The Great Cholesterol Lie” , “The”  Cholesterol Hoax”, The Cholesterol Scam”  abound .

These sites proclaim that cholesterol is a vital component of cell membranes (it is) and that any attempt by diet or drugs to lower levels will result in severe side effects with no benefit

Doctors, according to these types of sites, in collusion with Big Pharma, have inflated the benefits of statin drugs and overlooked the side effects in the name of profit. Often, a “natural” alternative to statins is promoted.  In all cases a book is promoted.

The Great Cholesterol Truths

It’s unfortunate that nutritional guidelines have promoted restriction of cholesterol and fat for so long. These guidelines (like most of nutritional science)  were based on flawed observational studies. They should not have been made public policy without more consensus from the scientific community.  The good news is that ultimately the truth prevails when enough good scientific studies are done.

It is right to question the flimsy foundation of nutritional recommendations on diet and heart disease but the evidence for statin benefits in patients with established coronary heart disease is rock solid.

Hopefully, the less long-winded explanation I provided my patient in the office will persuade him to keep on taking his atorvastatin pills while simultaneously allowing him to eat eggs, shrimp and full fat dairy without guilt.

Calcium Supplements: Would You Rather Have a Hip Fracture or a Heart Attack?

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Does taking extra calcium pills contribute to the deposition of calcium into the coronary arteries that we see in CT scans like this?

Since I’ve been utilizing coronary calcium CT scans to detect early atherosclerotic plaque (see here) in my patients, I have frequently been asked about the relationship between calcium supplements and heart attack risk.

For example, Mrs. Jones has just found out that she has a very high calcium score and that it reflects the amount of atherosclerotic plaque lining and potentially clogging the coronary arteries to her heart. She has also been taking calcium and Vitamin D supplements recommended to her to prevent bone thinning and fractures in the future.

Did all that extra calcium she was consuming end up depositing in her coronary arteries, thus increasing her risk of heart disease?

This is a complex and not fully settled issue, however, there is enough evidence to suggest that we be cautious about calcium supplements.

A recent meta-analysis (Bolland MJ, Avenell A, Baron JA, Grey A, MacLennan GS, Gamble GD, et al. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis. BMJ 2010;341:c3691) of cardiovascular events in randomized, placebo controlled trials of calcium supplements (without vitamin D co-administration) showed that calcium supplements significantly increased the risk of myocardial infarction by 31% in five trials involving 8151 participants.

A recent meta-analysis of trials involving calcium and Vitamin D supplements found a similar increased risk of cardiovascular disease in the subjects randomized to taking calcium and Vitamin D.

These authors concluded

“in our analysis, treating 1000 patients with calcium or calcium and vitamin D for five years would cause an additional six myocardial infarctions or strokes (number needed to harm of 178) and prevent only three fractures (number needed to treat of 302”

How Might Calcium Supplements Increase Cardiovascular Risks?

Calcium supplements acutely and chronically  increase serum calcium concentration. Higher calcium levels are associated with more carotid artery plaque, aortic calcification, and  a higher incidence of heart attack and death.

Just like atherosclerosis, the process of calcium deposition into the arteries is very complex. Higher calcium levels could alter certain regulators of the process, such as fetuin A, pyrophosphate and bone morphogenic protein-7 or bind to calcium receptors on vascular smooth muscle cells lining the arteries

Higher calcium levels may also promote clot formation.

Bone Fracture versus Heart Attack

The informed doctor would have to tell Mrs. Jones that her calcium supplements may have contributed to her advanced coronary calcium and raised her risk of heart attack and stroke.

As with all medications, she and her doctor are going to have to discuss the relative risks and benefits.

If she has great concerns about fractures and has very low bone mineral bone density (osteoporosis) along with no family history of premature heart disease then the calcium supplementation may be appropriate.

Conversely, if she has high risk factors for coronary heart disease and/or a strong family history of premature coronary heart disease and only slightly low bone mineral density, avoiding the calcium supplements would be appropriate.

Preventing Fractures and Heart Attacks

It’s best to get calcium from the foods we eat rather than a sudden concentrated load of a supplement. Full fat dairy products like yogurt and cheese are heart healthy (see here and here) and they are an excellent source of calcium.

Weight-bearing exercise (such as running/jogging/hiking) and strength-building exercise (lifting weights, resistance machines, etc.) are also important for strengthening bones.

Thus, eating full fat dairy and aerobic exercise will help prevent both a fracture and a heart attack.

Happy Thanksgiving: UpToDate Says Don’t Worry About Saturated Fat Consumption

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UpToDate now says high fat dairy OK!

Despite mounting evidence to the contrary, mainstream nutritional guidelines have, for the last 30 years, instructed Americans to reduce fat and, more specifically, saturated fat in their diets.

As I have written here and here, that advice is not supported by the bulk of evidence and is being challenged. Despite this, the USDA guidelines and the American Heart Association guidelines continue to recommend reducing fat intake.

On October 26, 2014 a highly respected online resource called UpToDate changed its recommendations in this area. I became aware of this when I found an outstanding blog post by Dr. Axel Sigurdsson. Dr. Sigurdsson is a cardiologist and the former president of the Icelandic Cardiac Society who writes a blog called Doc’s Opinion; his recent post is titled: “About Heart Disease, Nutrition, Healthy Lifestyle and Prevention of Disease.”

His post, entitled “We no longer recommend avoiding saturated fats per se” provides an outstanding summary of the importance of the change and I highly recommend reading it.

UpToDate is by far the most commonly utilized online clinical decision resource in the world. A recent paper surveyed physicians and found that

the 4 most frequently used resources were online journals (46%), PubMed/MEDLINE (42%), UpToDate(40%), and online books (30%). The overall rating for UpToDate was high due to the large proportion of residents who reported using this resource (77%).

My hospital pays for a subscription to UpToDate and the medical staff and residents (doctors in training) use it very frequently to access the latest information on preventing, diagnosing and treating diseases.  Hopefully, since the residents represent the future of medicine, these changed dietary recommendations will become more widespread and become the dominant nutritional message to the public.

The UpToDate authors wrote:

“Although it is known that there is a continuous graded relationship between serum cholesterol concentration and coronary heart disease (CHD), and that dietary intake of saturated fats raises total serum cholesterol, a 2014 meta-analysis of prospective observational studies found no association between intake of saturated fat and risk for CHD.

The meta-analysis also found no relationship between monounsaturated fat intake and CHD, but suggested a reduction in CHD with higher intake of omega-3 polyunsaturated fats; a benefit with omega-6 polyunsaturated fats remains uncertain.

Given these results, we no longer suggest avoiding saturated fats per se, although many foods high in saturated fats are less healthy than foods containing lower levels.

In particular, we no longer feel there is substantial evidence for choosing dairy products based on low-fat content (such as choosing skim milk in preference to higher fat milk). We continue to advise reducing intake of trans fatty acids.”

I’m particularly happy to see this change with respect to dairy products because I think the switch to non or low fat diary has been deleterious to Americans’ health and is not supported by data.

As Dr. Sigurdsson observes:

Today, blaming the rising incidence of coronary heart disease 40-50 years ago on the intake of red meat, whole-fat milk, cheese, cream, butter and eggs appears naive at best.

To condemn one macronutrient and suggest it be replaced with another, without having any scientific evidence that such and intervention is helpful, would today be considered careless and irresponsible.

Sticking with the same conclusion for 40 years, despite abundant contradictory evidence is shocking and hard to understand. Hopefully, UpToDate’s recent reconsideration of the issue is a sign that the tide is turning.

Of course, there’s no reason to promote high consumption of saturated fats and surely there will often be healthier options. However, it’s time we stop telling people that avoiding saturated fats may protect them from heart disease. Why should we say such a thing if it’s not supported by evidence?

It will be interesting to see how public authorities such as the American Heart Association will react to recent scientific evidence on the proposed link between saturated fats and coronary artery disease. Will we see a change in the forthcoming 2015 version of The Dietary Guidelines for Americans?

Will their approach be evidence-based or not? Will they accept that red meat, whole-fat milk, cheese, cream, butter and eggs can be a part of a healthy diet? Will they reconsider their recommendations as UpToDate has now officially done? Only time will tell.